Abstract:

Claims:

15. An aerosol dispensing system comprising a sealed container equipped
with an aerosol dispensing valve and a propellant comprising at least one
h drofluorocarbon selected from the group consisting of:
CF3CH=CHCF3, CF3CH=CHC2F5,
CF3CH=CHCF2C2F5, CF3CH=CHCF(CF3)2,
C2F5CH=CHC2F5, CF3CH=CH(CF2)3CF3,
CF3CH=CHCF2CF(CF3)2,
CF3CH=CHCF(CF3)C2F5, CF3CH=CHC(CF3)3,
C2F5CH=CHCF2C2F5, and
C2F5CH=CHCF(CF3).sub.2.

16. (canceled)

17. (canceled)

18. (canceled)

19. (canceled)

20. The aerosol dispensing system of claim 15, wherein the propellant
consists essentially of the hydrofluorocarbon.

21. The aerosol dispensing system of claim 15, wherein the propellant has
a vapor pressure in a range of from about 138 to about 621 kPA at
21.degree. C.

22. The aerosol dispensing system of claim 15, wherein the aerosol is a
cleaner, duster, personal care product, automotive product, or
medicament.

Description:

CROSS REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims the benefit of priority to U.S. Provisional
Application No. 60/732,292, the complete disclosure of which is
incorporated herein by reference.

FIELD OF THE INVENTION

[0002] Disclosed herein are aerosol propellant compositions comprising
unsaturated fluorocarbons or unsaturated hydrofluorocarbons. Also
disclosed is the use of these compositions in preparing aerosol products.

BACKGROUND OF THE INVENTION

[0003] In the early 1970s, concern began to be expressed that the
stratospheric ozone layer (which provides protection against penetration
of the Earth's atmosphere by ultraviolet radiation) was being depleted by
chlorine atoms introduced to the atmosphere from the release of
chlorofluorocarbons. These chlorofluorocarbons were used as propellants
in aerosols, as blowing agents for foams, as refrigerants and as
cleaning/drying solvent systems. Because of the great chemical stability
of fully halogenated chlorofluorocarbons, according to the ozone
depletion theory, these compounds do not decompose in the Earth's
troposphere but reach the stratosphere where they slowly degrade
liberating chlorine atoms which in turn react with the ozone.

[0004] Concern reached such a level that in 1978 the U.S. Environmental
Protection Agency (EPA) placed a ban on nonessential uses of fully
halogenated chlorofluorocarbons (CFC) as aerosol propellants, and in 1995
banned nonessential uses of hydrochlorofluorocarbon (HCFC) propellants.

[0005] There is also a demand for aerosol propellants which have
significantly less photochemical reactivity than hydrocarbons that
contribute to the formation of ambient ozone and ground level smog. These
compounds are typically referred to as low-VOC (volatile organic
compound) or non-VOC.

[0006] The disclosure herein relates to the discovery of compositions,
which include unsaturated fluorocarbons and hydrofluorocarbons. These
compositions have zero ozone depletion potential (ODP), low global
warming potential (GWP) and are lower VOC than hydrocarbons. These
compositions are useful as pure components or in mixtures. These
compositions are used as aerosol propellants.

[0013] Further, when an amount, concentration, or other value or parameter
is given as either a range, preferred range, or a list of upper
preferable values and lower preferable values, this is to be understood
as specifically disclosing all ranges formed from any pair of any upper
range limit or preferred value and any lower range limit or preferred
value, regardless of whether ranges are separately disclosed. Where a
range of numerical values is recited herein, unless otherwise stated, the
range is intended to include the endpoints thereof, and all integers and
fractions within the range. It is not intended that the scope of the
invention be limited to the specific values recited when defining a
range.

[0014] One aspect relates to compositions useful in aerosol; i.e.,
pressurized, dispensing systems. The disclosure herein relates in
particular to the field of aerosol compositions which exhibit
environmental responsibility while retaining desirable properties
associated with aerosol dispensing systems.

[0015] There are numerous difficulties associated with formulating an
environmentally responsible propellant for use with an aerosol dispensing
system, including but not limited to achieving a single phase, soluble
composition which will retain desirable spray characteristics and product
performance characteristics of aerosols currently marketed. Flammability
is also a consideration. Also problematic in the formulation of personal
care products is obtaining a composition useful in dispensing active
ingredient from an aerosol dispensing system absent toxic side effects.

[0016] Aerosol products are generally preferred over products dispensed by
pumps or other systems. Many advantages of aerosols stem from the fact
that air is not drawn into the aerosol container to replace ingredients
dispensed. Thus the product is not exposed to deteriorating or oxidizing
effects of air and/or transient moisture, the product maintains its
sterility, and preservatives need not be included in the product
composition. Consumers prefer aerosols for their convenience, ease of use
and cleanliness. Broadly speaking, the characteristics of the spray
dispensed from aerosol systems are superior to those of other systems.
The product composition is generally applied with a finer, more even
spray than when applied with pump sprays. Pump-type dispensers tend to
over-concentrate the product in one spot because of inability to maintain
uniformity of product dispersal throughout the target area. This is
important, for example, in a hairspray product where it is desirable that
the spray retain manageability and hold of the hair style yet not weigh
the hair down, give an unnatural hold, or feel sticky to touch.

[0017] It is, therefore, desirable to develop a homogeneous, soluble and
nontoxic composition with limited flammability, useful in an aerosol
dispensing system for personal care as well as other products, which
retains advantageous spray characteristics and other properties of an
aerosol, while achieving environmental responsibility.

[0018] Accordingly, one aspect to provide a composition useful in an
aerosol dispensing system which achieves the advantageous properties of
an aerosol.

[0019] A further object to provide a sealed container with an aerosol
dispensing system and a composition which attains the objectives
described herein.

[0020] The foregoing objectives are achieved with the unsaturated
fluorocarbon and hydrofluorocarbon propellant compositions disclosed
herein. The compositions may be formulated with active ingredient from
about 1-15% by weight, or more. Total propellant may vary from 15-95%.

[0021] Also contemplated is an aerosol dispensing system comprising a
sealed container equipped with an aerosol dispensing valve and containing
therein the composition and active ingredient as above.

[0022] An important physical property associated with the dispensing of
aerosol products is the vapor pressure of the propellant. By "vapor
pressure" is meant the pressure exerted when a liquefied propellant gas
is in equilibrium with its vapor in a closed container, such as an
aerosol can. Vapor pressure can be measured by connecting a pressure
gauge to the valve on an aerosol can or gas cylinder containing the
vapor/liquid mixture. A standard of measurement of vapor pressure in the
U.S. aerosol industry is pounds per square inch gauge (psig) with the
gas/liquefied mixture at constant temperature, most commonly at
70° F. (21° C.). The vapor pressure of liquefied gases most
widely employed as aerosol propellants will vary over the range of about
20 to 90 psig (138 to 621 kPa) at 70° F. (21° C.). The
propellant systems disclosed herein have vapor pressures in this range.

[0023] One aspect encompasses non-toxic compositions useful in an aerosol
dispensing system. The compositions comprise unsaturated fluorocarbons
(FCs) and/or hydrofluorocarbons (HFCs) alone or in mixture with each
other or other suitable propellants, including saturated HFCs,
hydrocarbons (HCs), dimethylether, carbon dioxide, nitrous oxide, and
nitrogen. Optional active ingredients and additives may be included in
the formulation in order to prepare different forms of end products by
numerous methods known to those skilled in the art.

[0025] Compounds of Formula I may be prepared by contacting a
perfluoroalkyl iodide of the formula R1I with a
perfluoroalkyltrihydroolefin of the formula R2CH=CH2 to form a
trihydroiodoperfluoroalkane of the formula R1CH2CHIR2.
This trihydroiodoperfluoroalkane can then be dehydroiodinated to form
R1CH=CHR2. Alternatively, the olefin R1CH=CHR2 may be
prepared by dehydroiodination of a trihydroiodoperfluoroalkane of the
formula R1CHICH2R2 formed in turn by reacting a
perfluoroalkyl iodide of the formula R2I with a
perfluoroalkyltrihydroolefin of the formula R1CH=CH2.

[0026] Said contacting of a perfluoroalkyl iodide with a
perfluoroalkyltrihydroolefin may take place in batch mode by combining
the reactants in a suitable reaction vessel capable of operating under
the autogenous pressure of the reactants and products at reaction
temperature. Suitable reaction vessels include fabricated from stainless
steels, in particular of the austenitic type, and the well-known high
nickel alloys such as Monel® nickel-copper alloys, Hastelloy®
nickel based alloys and Inconel® nickel-chromium alloys.

[0027] Alternatively, the reaction may take be conducted in semi-batch
mode in which the perfluoroalkyltrihydroolefin reactant is added to the
perfluoroalkyl iodide reactant by means of a suitable addition apparatus
such as a pump at the reaction temperature.

[0028] The ratio of perfluoroalkyl iodide to perfluoroalkyltrihydroolefin
should be between about 1:1 to about 4:1, preferably from about 1.5:1 to
2.5:1. Ratios less than 1.5:1 tend to result in large amounts of the 2:1
adduct as reported by Jeanneaux, et al. in Journal of Fluorine Chemistry,
Vol. 4, pages 261-270 (1974).

[0029] Preferred temperatures for contacting of said perfluoroalkyl iodide
with said perfluoroalkyltrihydroolefin are preferably within the range of
about 150° C. to 300° C., preferably from about 170°
C. to about 250° C., and most preferably from about 180° C.
to about 230° C.

[0030] Suitable contact times for the reaction of the perfluoroalkyl
iodide with the perfluoroalkyltrihydroolefin are from about 0.5 hour to
18 hours, preferably from about 4 to about 12 hours.

[0031] The trihydroiodoperfluoroalkane prepared by reaction of the
perfluoroalkyl iodide with the perfluoroalkyltrihydroolefin may be used
directly in the dehydroiodination step or may preferably be recovered and
purified by distilled prior to the dehydroiodination step.

[0033] Said contacting of the trihydroiodoperfluoroalkane with a basic
substance may take place in the liquid phase preferably in the presence
of a solvent capable of dissolving at least a portion of both reactants.
Solvents suitable for the dehydroiodination step include one or more
polar organic solvents such as alcohols (e.g., methanol, ethanol,
n-propanol, isopropanol, n-butanol, isobutanol, and tertiary butanol),
nitriles (e.g., acetonitrile, propionitrile, butyronitrile, benzonitrile,
or adiponitrile), dimethyl sulfoxide, N,N-dimethylformamide,
N,N-dimethylacetamide, or sulfolane. The choice of solvent may depend on
the boiling point product and the ease of separation of traces of the
solvent from the product during purification. Typically, ethanol or
isopropanol are good solvents for the reaction.

[0034] Typically, the dehydroiodination reaction may be carried out by
addition of one of the reactants (either the basic substance or the
trihydroiodoperfluoroalkane) to the other reactant in a suitable reaction
vessel. Said reaction may be fabricated from glass, ceramic, or metal and
is preferably agitated with an impellor or stirring mechanism.

[0035] Temperatures suitable for the dehydroiodination reaction are from
about 10° C. to about 100° C., preferably from about
20° C. to about 70° C. The dehydroiodination reaction may
be carried out at ambient pressure or at reduced or elevated pressure. Of
note are dehydroiodination reactions in which the compound of Formula I
is distilled out of the reaction vessel as it is formed.

[0037] Alternatively, the dehydroiodination reaction may be conducted in
the absence of solvent by adding the trihydroiodoperfluoroalkane to a
solid or liquid basic substances.

[0038] Suitable reaction times for the dehydroiodination reactions are
from about 15 minutes to about six hours or more depending on the
solubility of the reactants. Typically the dehydroiodination reaction is
rapid and requires about 30 minutes to about three hours for completion.

[0039] The compound of formula I may be recovered from the
dehydroiodination reaction mixture by phase separation after addition of
water, by distillation, or by a combination thereof.

[0040] The compositions disclosed herein may comprise a single compound of
Formula I, for example, one of the compounds in Table 1, or may comprise
a combination of compounds of Formula I.

[0041] In addition to the inventive compounds described above, compounds
presented in Table 2 can be used as aerosol propellants.

[0044] The compounds listed in Table 3 are available commercially or may
be prepared by processes known in the art.

[0045] 1-Bromo-3,3,4,4,4-pentafluoro-1-butene may be prepared by a three
step sequence beginning with reaction of phosphorous tribromide with
3,3,4,4,4-pentafluoro-1-butanol to give
4-bromo-1,1,1,2,2-pentafluorobutane. Thermal bromination of
4-bromo-1,1,1,2,2-pentafluorobutane at 350-400° C. gives
4,4-dibromo-1,1,1,2,2-pentafluorobutane which may in turn be heated with
powdered potassium hydroxide to give the desired bromobutene.

[0046] 2-Bromo-3,4,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene may be
prepared by addition of bromine to
3,4,4-tetrafluoro-3-(trifluoromethyl)-1-butene followed by treatment of
the resulting dibromide with ethanolic potassium hydroxide.

[0047] Many of the compounds of Formulas I, Table 1, Table 2 and Table 3
exist as different configurational isomers or stereoisomers. When the
specific isomer is not designated, the disclosure herein is intended to
include all single configurational isomers, single stereoisomers, or any
combination thereof. For instance, CF3CH=CHCF3 is meant to
represent the E-isomer, Z-isomer, or any combination or mixture of both
isomers in any ratio. Another example is
C2F5CF2CH=CH--CF2C2F5, by which is
represented the E-isomer, Z-isomer, or any combination or mixture of both
isomers in any ratio.

[0048] Aerosol propellants may comprise a single compound as listed, for
example, in Table 2, or may comprise a combination of compounds from
Table 2 or, alternatively, a combination of compounds from Table 1, Table
2, Table 3, and/or Formula I.

[0049] The amount of the fluorocarbons (FCs) or HFCs contained in the
present compositions (from, e.g., Formula I, Table 1, or Table 2, or
Table 3) can vary widely, depending the particular application, and
compositions containing more than trace amounts and less than 100% of the
compound are within broad the scope of the present disclosure.
Preferably, the compositions have a Global Warming Potential (GWP) of not
greater than 150, more preferably not greater than 100, and even more
preferably not greater than 75. As used herein, "GWP" is measured
relative to that of carbon dioxide and over a 100-year time horizon, as
defined in "The Scientific Assessment of Ozone Depletion, 2002, a report
of the World Meteorological Association's Global Ozone Research and
Monitoring Project," which is incorporated herein by reference.

[0050] The present compositions also preferably have an Ozone Depletion
Potential (ODP) of not greater than 0.05, more preferably not greater
than 0.02 and even more preferably about zero. As used herein, "ODP" is
as defined in "The Scientific Assessment of Ozone Depletion, 2002, A
report of the World Meteorological Association's Global Ozone Research
and Monitoring Project," which is incorporated herein by reference.

[0051] The compositions may be prepared by any convenient method to
combine the desired amounts of the individual components. A preferred
method is to weigh the desired component amounts and thereafter combine
the components in an appropriate vessel. Agitation may be used, if
desired.

[0052] The propellants may comprise a single compound as listed, for
example, in Table 1, or may comprise a combination of compounds of
Formula I, Table 1, Table 2, and/or Table 3. Additionally, many of the
compounds described herein may exist as different configurational isomers
or stereoisomers. The disclosure herein is intended to include all single
configurational isomers, single stereoisomers, or any combination
thereof. For instance, F11E is meant to represent the E-isomer, Z-isomer,
or any combination or mixture of both isomers in any ratio. Another
example is F33E, by which is represented the E-isomer, Z-isomer, or any
combination or mixture of both isomers in any ratio.

[0053] Preferably, the propellants disclosed herein have a Global Warming
Potential (GWP) of not greater than 150, more preferably not greater than
100, and even more preferably not greater than 75. As used herein, "GWP"
is measured relative to that of carbon dioxide and over a 100-year time
horizon, as defined in "The Scientific Assessment of Ozone Depletion,
2002, a report of the World Meteorological Association's Global Ozone
Research and Monitoring Project," which is incorporated herein by
reference.

[0054] The present compositions also preferably have an Ozone Depletion
Potential (ODP) of not greater than 0.05, more preferably not greater
than 0.02 and even more preferably about zero. As used herein, "ODP" is
as defined in "The Scientific Assessment of Ozone Depletion, 2002, A
report of the World Meteorological Association's Global Ozone Research
and Monitoring Project," which is incorporated herein by reference.

[0055] The compositions may be prepared by any convenient method to
combine the desired amounts of the individual components. A preferred
method is to weigh the desired component amounts and thereafter combine
the components in an appropriate vessel. Agitation may be used, if
desired.

[0056] The propellant composition comprises, more preferably consists
essentially of, and, even more preferably, consists of compositions
disclosed herein. The active ingredient to be sprayed together with inert
ingredients, solvents, and other materials may also be present in the
sprayable mixture. Preferably, the sprayable composition is an aerosol.

[0057] Another embodiment of the present disclosure provides a process for
producing aerosol products comprising the step of adding a composition as
disclosed herein to active ingredients in an aerosol container, wherein
said composition functions as a propellant.

[0058] The compositions are capable of providing nonflammable, liquefied
gas propellant and aerosols that do not contribute substantially to
global warming. The present compositions can be used to formulate a
variety of industrial aerosols or other sprayable compositions such as
contact cleaners, dusters, lubricant sprays, mold release sprays, and the
like, and consumer aerosols such as personal care products (such as,
e.g., hair sprays, deodorants, and perfumes), household products (such
as, e.g., waxes, polishes, pan sprays, room fresheners, and household
insecticides), and automotive products (such as, e.g., cleaners and
polishers), as well as medicinal materials such as anti-asthma and
anti-halitosis medications. Examples of this includes metered dose
inhalers (MDIs) for the treatment of asthma and other chronic obstructive
pulmonary diseases and for delivery of medicaments to accessible mucous
membranes or intranasally.

[0059] All such products utilize the pressure of a propellant gas or a
mixture of propellant gases (i.e., a propellant gas system) to expel
active ingredients from the container. For this purpose, most aerosols
employ liquefied gases which vaporize and provide the pressure to propel
the active ingredients when the valve on the aerosol container is pressed
open.

[0060] The medicinal aerosol and/or propellant and/or sprayable
compositions in many applications include, in addition to a compound
disclosed herein, a medicament such as a beta-agonist, a corticosteroid
or other medicament, and, optionally, other ingredients, such as
surfactants, solvents, other propellants, flavorants, and other
excipients. The compositions disclosed herein, unlike many compositions
previously used in these applications, have good environmental properties
and are not considered to be potential contributors to global warming.
The present compositions therefore provide in certain preferred
embodiments substantially nonflammable, liquefied gas propellants having
very low GWPs.

[0061] All of the compositions and methods disclosed and claimed herein
can be made and executed without undue experimentation in light of the
present disclosure. While the compositions and methods disclosed herein
have been described in terms of preferred embodiments, it will be
apparent to those of skill in the art that variations may be applied to
the compositions and methods and in the steps or in the sequence of steps
of the method described herein without departing from the concept,
spirit, and scope of the present disclosure. More specifically, it will
be apparent that certain agents which are chemically related may be
substituted for the agents described herein while the same or similar
results would be achieved. All such similar substitutes and modifications
apparent to those skilled in the art are deemed to be within the spirit,
scope, and concept of the present disclosure as defined by the appended
claims.

EXAMPLES

[0062] The present disclosure is further defined in the following
Examples. It should be understood that these Examples, while indicating
preferred embodiments, are given by way of illustration only. From the
above discussion and these Examples, one skilled in the art can ascertain
the preferred features, and without departing from the spirit and scope
thereof, can make various changes and modifications to adapt it to
various uses and conditions.